Exposition Medal

Unknown William McKinley medal?
It’s driving me nuts. I dug up this coin/medal/token when I was a kid and I’ve never been able to figure out what it is, what it’s worth, where it came from ext. Trust me I have looked, and looked but anyway…
The front says:
25th President, U.S.A.
1897 -1901
Assassinated
William McKinley
The back says:
“Little Mack”
Major
In civil war
Congressman
Governor of Ohio
Served as President
Throughout
War with Spain
Assassinated
At Pan American
Exposition in
Buffalo
“Our Martyred President”
I am willing ot bet it was a commemorative coin made sometime shortly after McKinley was assassinated by a man name Charles Guiteau. Not sure of the spelling.
Believe they had similar type commemorative for Lincoln as well but I believe his was a small picture with a black ribbon.
It was not minted as legal tender but if it is in good shape, it should be worth some small amount. Probably tens of thousands of them were made.
Herbert James Draper. Sirènes. Claude Debussy.